This invention generally relates to systems and processes for repairing composite structures, and in particular, to systems and processes for effecting such repairs at a site with participation by an off-site repair expert.
The use of structures comprised of composite materials has grown in popularity, particularly in such applications as aircraft airframes, where benefits include increased strength and rigidity, reduced weight and reduced parts count. When damaged, however, composite structures often require extensive repair work which may ground an aircraft, thereby adding significantly to the support costs of the aircraft. Current maintenance procedures frequently require that the damaged component be removed and replaced before the aircraft can resume flying. Repairs to composite structures can be complicated and time consuming. Currently, many line mechanics do not generally have the training and experience to perform composite repairs.
The current process for repairing graphite/epoxy primary and secondary structures requires extensive preparation and multiple process steps to perform acceptable composite repairs. For example, a typical repair process involves scarfing the area around the defect, orienting and nesting a stack of repair plies made of composite material in the scarfed area, bagging the repair site, and subjecting the repair plies to vacuum and heating to consolidate and cure the composite material of the repair plies.
Often significant time is taken to perform the scarfing operations correctly because a technician is unfamiliar with the process. During manual scarfing, the technician usually relies on the visual shapes of the ply boundaries to determine how much composite material to scarf away. Errors may be introduced by the technician during scarfing or other operations (e.g., while orienting and nesting plies, during bagging or curing). For automated/robotic scarfing, errors may be introduced by the technician during set-up of the automated system. It would be advantageous to have an expert provide guidance and feedback during the entire repair process, yet it is costly to have a seasoned repair expert on site for each repair